Lightning-arrester.



E. R. HARDING.

LIGHTNING ARRESTER.

APPLICATION FILED JULY 5, 1907.

Patented Feb. 21, 1911.

THE "01mm rsrzres ca WASHINGTON, n. c.

EDWIN R. HARDING, OF CHICAGO, ILLINOIS.

LIGHTN IN G-ARRESTER.

Specification of Letters Patent.

Application filed July 5, 1907.

Patented Feb. 21, 1911. Serial No. 382,180.

To all whom it may concern:

Be it: known that I, EDWIN R. I'IARDING, a citizen of the United. States of America, and resident of Chicago, Cook county, Illinois, have invented a certain new and useful Improvement in Light]iing-Arresters, of which the following is a specification.

My invention relates to lightning-arresters for use in telephone and other systems. Devices of this character are, for example, employed at the subscribers telephones for )reventing lightnin from in uring the in K. D n/ struments.

It. relates more particularly to that type of lightning-arrester in which means are provided for jumpii'ig the static charge from the telephone line circuit: to a piece of warbon, which is in turn connected with ground. In this way, normal currents can pass over the circuit without going to the ground, but the abnormal charge of the lightning stroke will be instantly grounded.

More especially, my invention relates to lightningarrcsters of this type in which one or more choke coils of uninsulated or only slightly insulated wire are connected in the line circuit and arranged with the convolutions thereof in close proximity to a piece of carbon, whereby the lightning or other static charge will tind a plurality of points from which itcan jump to the carbon. In other words, in a lightning-arrester of this character the abnormal charge traverses the convolutions of the wire coil, owing to the choking effect, caused by self-induction, the latter being of such length that, owing to the choking effect caused by sclf-induction, the entire charge will have jumped to ground before it can pass entirely through the coil and enter the instruments or apparatus which it is desired to protect. So far as I am aware. these arresters have been found to be satisfactory and desirable in some ways. but in other ways they have not proven satisfactory. For example, prior to my invention all. lightning-arresters operated on this principle have either been so constructed that the coil or coils of wire could not be inserted and replaced independently of the carbon or other substanc used for groundingthat is to say. the carbon and the coil or coils were either united in a unitary structure, or if removable were. not adjustable to bring different sides of the coils into proximity to the carbon. Again, the coils were often of such character as to retard the voice currents, being made with wire cores to give the choking effect when lightning comes on the line. For this reason it was not possible to remove the carbon without removing the coils, nor was it possible to remove the coil or coils without removing the carbon, and if removable then the coils were subject to the other disadvantages stated. Again, in some devices of this kind employed prior to my invention, the coil or coils and the carbon or other substance used for grounding were so relatively disposed that clogging and impairment of the arrester were liable, owing to the fact that the gaps between the carbon or other substance used for grounding and the convolutions of the wire were not accessible for purposes of cleaning. Consequently, many of the devices heretofore employed of this character were liable to become ineflicient as a protecting means, and were liable to cause an undesirable short-circuiting or grounding of the line circuit in which they were employed; and if not subject to this trouble. then the devices used prior to my invention were open to objections for other reasons. These and other disadvantages and objections have been characteristic, more or less, of all the protectors heretofore constructed and operated on this principle.

Generally stated. therefore, the object of my invention is the provision of an improved and highly efficient lightning-arrester of the foregoing character.

Special objects of my invention are the provision of a. lightningarrester in which one or more wire coils are arranged with the convolutions thereof in close proximity to a grounded member, such as a piece of carbon, or other conducting material used for grounding. and in which the said coil or coils and the grounded member are each separately and readily removable from the arrester for purposes of repair or substitution, and each adjustable to bring fresh surface into play: the provision of a lightning-arrester of this particular character in which the carbon. or other grounded member is arranged externally of the readily removable coil or coils, and in close proximityto the periphery or outer circumference of said coil. or coils, whereby the air gaps between the carbon and the convolut-ions of the coil or coils are readily accessible for purposes of cleaning, thereby rendering it comparatiyely easy to prevent clogging or impairment of the arrester, and in which said coils have their convolutions so closely arranged as to develop su'tlicient self-induction without using iron cores; and the provision of certain details and features of improvement and combinations tending to increase the:

section on line in Fig. 1. Fig. 3 is a section on lme 33 in Fig. 1. Fig. t is a perspective oi one of the terminals for the coils. Fig. 5 is a perspective of one of the terminals for the carbon. Fig. (3 is a perspective of one of the spring clips by which the glass cover is held in place. Fig. 7 is asection on line 'T7 in Fig. 1.

As thus illustrated, my improved light ning-arrester comprises a base A of any suit able insulatingmaterial. Upon the said base are mounted the four line terminals B. C, D and each of which is :tormed and constructed substantially as shown in Fig. 4. As illustrated. the terminal B comprises a base portion c. which is secured to the base A by a screw c and a washer (See Fig. 3 and the like parts of terminal C.) The line wire can be secured in the opening 0 by the screw 0*. thus giving a binding post connection. The said terminal has two upwardly extending cheeks or springing por' tions c, each provided with an inwardly bent portion c. as illustrated. It also has a lug which engages in a recess in the base A to prevent the terminal C from twisting around. It will be understood that the other three terminals C. D and E are similarly constructed. They are arranged in line. two at each side of the carbon F, as shown in the drawings. The said carbon is cylindric in term, and is held in the clips or terminals G and H. These two terminals are similar, the terminal H, for example, as shown in Fig. 5, consisting ot a, body portion 71' which sets in the base A. and which is held in place by a screw 7L1 and a. washer 7L2. as shown in Fig. 7. Said terminal H has an upper screw 71. by which a ground wire can be held in the opening 71* in the body portion It. as shown in the drawings. It will also be seen that the terminal H has a couple of checks or up wardly bent portions if each provided with an inwardly bent portion 71.. The terminal G is similarly constructed. and the spring clips I and .T are clamped in place by the said terminals, by means of screws 71 and 7' which extend upwardly through the base A and have screw-threaded engagement with the said terminals Gr and H, as shown more clearly in Fig. 2 of the drawings. Vith this arrangement the said spring clips are adapted to hold the glass cover K in place to protect the lightning-arr-ester against dust. short circuit and the like. The portions h, and the similar portions on the terminal G, are adapted to support the carbon F, to prevent the carbon from dropping to the bottom of the terminals.

The removable coils L and M each eonsist ot' a length of copper wire wound upon a lava cylinder or other insulating material, as, for example the roll Z of the coil L. llletal pins Z" are inserted in the ends of the said cylinder of la "a to 'lorm the terminals of the said coil L. The cylinder of lava and the wire may then be given a thin coating of shellac. or like material. and it will be observed that the convolutions ot the coil are separated. It will be understood that the coil N is similarly constructed and that by the terminal pieces l). t. D and E the two coils can be included in opposite sides of a line circuit. such. for example. as that of an ordinary telephone line. It will also be seen that the construction is such that the convolutions of the two coils a re arranged in close proximity to the cylindric outer surface of the carbon F. so that each coil in eli'ect provides a plurality of points from which a static charge. such as a lightning stroke. can jump to the carbon and then find a path to earth. Preferably the two coils are arranged as close to the carbon as may be found possible without causing the coils to actually make contact with the carbon. The air gaps thus provided between the outer ruiriphery of each convolution and the outer circumference of the carbon are easily accessible. so that these air gaps can be kept clean and tree from substances which would tend to clog or impair the etliciency ot' the arrester. Each coil can be readily removed and cleaned, and this is also true of the carbon. The number of convolutions and the length of each coil are preferably such that a static charge. such a stroke of lightning. will have entirely jumped to earth before traversing the entire length of the coil, thus making it impossible for lightning to pass entirely through the coils and enter the instruments which it is desired to protect. The

coils can be readily removed without disturbing the carbon. and the carbon can be readily removed without disturbing the coils. The connections are easily made and broken. consequently the arrester easily adjusted in position for use or removed therefrom. It will be understood. of course. that the end portions of the wire or coil L are electrically united with the metal pins P. which latter rest in the terminals B and being supported by the portions 0 with which the terminal 13 is provided. and by the similar portions provided in the termi- .it is attached, and the coils and the carbon nal C. The coil N is similarly constructed and similarly supported in the terminals D and E, as illustrated. The coils and the carbon are all arranged parallel and lengthwise of the base A, and preferably in the same horizontal plane. The character of the coils is preferably such that they tend to choke back the lightning or other static charge, whereby the abnormal charge will l be induced to jump readily to the carbon where it finds an easy path to earth. Furthermore, it will be seen that means are provided for grounding the opposite ends of the carbon F, whereby a static charge in jumping across from one end of a coil will not be compelled to traverse the entire length of the carbon before escaping to the ground connection. \Vith this arrangement the carbon is preferably longer than the coils, so that the full length of each coil is brought into close proximity to the carbon, thus providing a plurality of points from which a static charge can jump across from either coil to the carbon.

From the foregoing it will be seen that I provide an improved and highly eflicient lightning arrester which is of a character to afford ample protection, which can be manufactured at a comparatively small cost, and which can be easily cleaned and inspected, and maintained in condition to insure the desired protection for the telephones or other apparatus.

It will be seen that the binding posts all extend upwardly through the base, and that the latter has its upper surface provided with grooves X that lead inwardly to these l'iinding posts, whereby the circuit wires may pass underneath the lower edges of the cover K. Thus the carbon and the coils are all. rotatable and upwardly removable from their supporting devices, and the cover is also upwardly removable, notwithstanding that the circuit connections are all made through the sides of the base. In this way the cover can be removed, and the connections can be made or broken without removing the base fronrany support to which can also be readily removed for the purpose of cleaning or repair. The coils and carbon are easily adjustable to bring fresh surfaces into use.

hat I claim as my invention is:

1. A lightning-arrester comprising a coil of wire, a strip of carbon arranged at one side of said coil and in close proximity to the convolutions thereof, a diamagnetic core for said coil, adapted to support the convolutions in inductive relation to each other, and metal circuit terminals for the ends of said coil, mounted in the ends of said core.

2. A lightning-arrester comprising a pair of line terminals, a coil removably mounted in said terminals, another pair of terminals,

a second coil mounted in said additional terminals, a pair of ground terminals and a carbon mounted in said ground terminals, readily adjustable therein and removable outwardly therefrom, said carbon disposed between said coils and in close proximity to the convolutions thereof.

3. A lightning-arrester comprising a cou ple of cylinders of non-fusible insulating material, a metal. pin in each end of each cylinder, terminal pieces for engaging said pins, a coil of wire on each cylinder of lava or insulating material, each coil of wire having the ends thereof electrically united to the pins in the ends of the cylinder, and the convolutions of each coil being close together, a cylinderof carbon disposed between said coils and in close proximity to the convolutions thereof, and means for making suitable connections with said carbon.

4. A lightniug-a-rrester comprising a pair of coils, a coat of suitable adhesive material on said coils to protect and hold the convolutions thereof in place, a. cylinder of -arbon adjustably disposed between said coils and in close proximity to the convolutions thereof, the convolutions of the coils being only very slightly separated, and means for establishing connections with the said coils and carbon.

In a lightning-arrester, the combination of two parallel coils of wire, and a cylindric length of carbon interposed between said coils and arranged in close proximity to the convolutions thereof, said carbon being adjustable endwise and longer than the said coils and rotatable relative thereto.

6. In a lightning-arrester, the combination of a pair of parallel coils, a length of carbon interposed between said coils and arranged in close proximity to the convolutions thereof, means whereby the coils are each removable without disturbing the carbon or the other coil, and means whereby the said carbon is removable without disturbing either of said coils, the carbon and coils being rotatable relative to each other.

7. A lightning-arrester comprising a pair of removable coils, and a ground-member interposed bet-ween said coils, substantially in the same plane therewith, removable outwardly and rotatable to bring fresh surface into use, and in close proximity to the convolutions thereof, each coil being rotatable to bring fresh portions thereof into use.

8. A lightning-arrester comprisin a pair of line terminals, a coil remova-bly mounted in said terminals, another pair of terminals, a second coil mounted in said additional terminals, a pair of ground terminals, and a groundanemb'er mounted in said ground terminals, said ground-member disposed between said coils, substantially in the same plane therewith, removable outwardly and rotatable to bring fresh surface into use, and

in close proximity to the convolutions thereof, each coil provided with a diamagnetic core having a smooth surface upon which the convolutions are only slightly separated, as set forth.

9. A lightning-arrester comprising. a couple of cylinders of insulating material, a metal pin in each end of each cylinder, terminal pieces for engaging said pins, each pin being round to rotate in its terminal, a coil of wire on each cylinder of insulating material, each coil of wire having the ends thereof electrically united to the pins in the end of the cylinder, a cylindric gronndmember disposed between said coils and in close proximity to the convolntions thereof, and means for making suitable connections with said ground-member.

10. A lightning-arrester comprising a pair of coils, diamagnetic cores therefor, a coat of adhesive material on said cores or coils to protect and hold the convolntions thereof in place, a ground-member disposed between said coils and in close proximity to the convolutions thereof. the convolutions of the coils being only slightly separated.

11. In a lightning-arrester, the combination of a pair of parallel coils. each coil rotatable about a longitudinal axis, a groundmember interposed between said coils and arranged in close proximity to the convolutions thereof substantially in the same plane Z therewith, means whereby the coils are each Qlth day 0t April 190;.

removable outwardly without disturbing the groundmember or the other coil, and means whereby the said ground-member is remov- 1 able outwardly without dlsturbnig either 12. In a lightning arrester, a base, bind ing posts in said base, spring sockets integral with said binding posts, a cylindric piece of carbon in two of said sockets, a coil at each side of said carbon, cylindric metal terminals for said coils, said terminals disposed in the remaining sockets, cylinders ot' insulation on which the coils are mounted, means for holding the coils in place on said insulation, and a cover setting over the coils and carbon, said base having grooves in the upper surface thereof in which wires are led to said binding posts.

13. In a lightning arr-ester, a removable cylindric carbon, and a removable coil at each side of said carbon, each coil and the carbon being adjustable by rotation thereot'.

let. In a lightning arrester, a carbon removable outwardly, and adjustable by rotation thereof, and a coil disposed at the side of said carbon, removable outwardly and adjustable by rotation thereof.

15. In a lightning arrester, a grounded member, a coil disposed at one side of said grounded member, a core of insulation for said coil, cylindric metal pins inserted in the ends of said core, longitudinally thereof, the oppositely projecting ends of said pins forming the terminals of said coil, and supporting means for removably engaging the sides of said pins to include the coil in circuit.

Signed by me at Chicago, Illinois, this EDIVIN It. HARDING. Vitnesses ALBERT JOHN Saosnn, NELLna CLEGG. 

